Flexible non-contact wound treatment device

ABSTRACT

A non-contact wound treatment device suitable for releasable attachment to a patient&#39;s skin surface over a selected wound area in a non-contact position relative to the selected wound area, the wound treatment device comprising an attachment portion suitable for releasable attachment with the patient&#39;s skin surface, having an inner perimeter for defining the selected wound area, a wound treatment portion with a substantially planar wound cover and a support member supporting the wound cover, and a transition portion with a membrane connecting the wound treatment portion to the attachment portion, the membrane extending around the outer perimeter of the support member and attached to the attachment portion between the inner and outer perimeter of the attachment portion.

CROSS REFERENCE TO RELATED CASES

This application is a Continuation-in-Part of co-pending U.S. Pat.application Ser. No. 08/342,741, filed Nov. 21, 1994 titled WOUNDTREATMENT DEVICE and having common assignee.

This application contains material related to the U.S. patentapplication filed on even date herewith that is entitled "FLEXIBLENON-CONTACT WOUND TREATMENT DEVICE WITH A SINGLE JOINT" and to thefollowing pending U.S. Patent Applications all assigned commonly withthis application:

Ser. No. 07/900,656, filed Jun. 19, 1992, for "THERMAL BODY TREATMENTAPPARATUS AND METHOD";

Ser. No. 08/356,325, filed Feb. 21, 1995, for "WOUND COVERING";

Ser. No. 08/785,794, filed Jan. 21, 1997, for "NORMOTHERMIC HEATER WOUNDCOVERING";

Ser. No. 08/786,713, filed Jan. 21, 1997, for "NORMOTHERMIC TISSUEHEATING WOUND COVERING";

Ser. No. 08/786,714, filed Jan. 21, 1997, for "NEAR HYPOTHERMIC HEATERWOUND COVERING".

TECHNICAL FIELD

This invention relates to a wound treatment device and, in particular,to a wound treatment device having a substantial portion of a woundcover that is in non-contact with a wound and capable of delivering heatto the wound. More particularly, the wound treatment device includes aflexion joint that maximizes the ability of the wound treatment deviceto adapt to the contours and movements of a human body.

BACKGROUND OF THE INVENTION

A novel mode of wound treatment is disclosed in detail in published PCTApplications WO 94/00090 and WO 96/15745, both owned in common with thisapplication. This new treatment employs a non-contact wound treatmentdevice that covers a wound, forming a treatment volume about and overthe wound. An embodiment of such a wound treatment device may becharacterized in having a plurality of parts, three of which are usefulfor the purpose of description. These three parts are an attachmentportion, a wound treatment portion, and a transition portion. Eachportion serves a respective function.

The attachment portion connects and retains the wound treatment deviceon the skin of a person. The wound treatment portion typically includesa standoff that rises above the person's skin surface, and a wound coverthat spans an open portion of the standoff. Together, the standoff andwound cover define a wound treatment volume and a wound treatment areaonto which the wound treatment volume is projected.

The transition portion connects the attachment portion to the woundtreatment portion. An important function of the transition portion is toadapt the wound treatment device to the contour of the portion of aperson's body where the device is mounted and to movements of theperson's body that deform the wound treatment device in situ. In thisregard, an important function of the transition portion is theaccommodation of patient motion by the compliance of the transitionportion.

Achievement of this important function of the transition portion ischallenged by the need to maintain the orientation of the wound cover inthe wound treatment portion--both in aspect and location--with respectto the wound being treated. The orientation of the wound cover isdifficult to maintain when the wound treatment device is mounted on ahighly curved part of a body. While the wound treatment devicesdisclosed in the referenced PCT applications exhibit excellentadaptability in a surface that is parallel to the surface of the bodyportion where the wound treatment device is mounted, there is impairmentof adaptability and disturbance of the orientation of the wound coverdue to limited flexibility in the direction of a Z axis that isperpendicular to the surfaces. If the transition portion issubstantially perpendicular to the attachment portion, it may buckle inresponse to body motion or contour and collapse the standoff in thewound treatment portion. The collapse of the standoff of course altersthe orientation of the wound cover with respect to the wound, possiblyreducing the effectiveness of the wound treatment device.

Z axis conformability is especially important for a wound treatmentdevice used on a portion of a person's lower leg. The lower leg has avery tight radius of curvature. Therefore, when a three-dimensionalwound treatment device is curved around a lower leg, substantial stressresults that may result in deformation of the shape of the woundtreatment device, in some cases even causing the wound cover to contactthe wound.

SUMMARY OF THE INVENTION

The overall flexibility of a wound treatment device is enhanced by aninvention based upon the inventors' critical realization that provisionof a membrane in the transition portion that connects the woundtreatment portion to the attachment portion accommodates patient motionand contour by paying out stored material to flex the wound treatmentdevice in all dimensions of the volume that the wound treatment deviceoccupies.

In this invention, the membrane connects the wound treatment portion tothe attachment portion, extending between the wound cover and theattachment portion, around the outside of an outer periphery of thestandoff in the wound treatment portion. Under the standoff, themembrane attaches to the attachment portion between inner and outerperipheries of the attachment portion.

Preferably, the inner periphery of the attachment portion along whichthe membrane is attached is limited to being contained within the outerperiphery of the standoff. This permits reduction of the size of theattachment portion, minimizing the total "foot print" of the woundtreatment device. A smaller footprint is generally considered to beadvantageous particularly when attaching the wound treatment device to ahighly curved part of a person's body, such as the surface of a lowerleg.

The membrane, its connection of the wound treatment portion with theattachment portion, and its attachment to the attachment portion alongan inner periphery of the attachment portion provide a flexion joint, ora double hinge that maximizes the adaptability of the wound treatmentdevice and maintains the orientation of the wound cover over greaterranges of body curvature and movement than previously obtainable.

It is, accordingly, an objective of this invention to provide aflexible, non-contact wound treatment device that adapts to bodycurvature and motion.

Another objective is the provision of a non-contact wound treatmentdevice having a wound treatment portion, an attachment portion, and atransition portion with a membrane connecting the wound treatment andattachment portions.

It is a related objective in this latter regard to provide a flexionjoint between the wound treatment and attachment portions in the form ofa membrane in the transition portion.

A significant advantage of the invention is the potential reduction insize of the attachment portion, providing a smaller footprint of thewound treatment device.

BRIEF DESCRIPTION OF THE DRAWINGS

The various figures of the drawing depict illustrative and exemplaryforms of the wound treatment device. Throughout the several views,identical reference characters represent similar or equivalentstructures wherein:

FIG. 1 is a perspective view of one embodiment of the wound treatmentdevice;

FIG. 2 is a schematic view of projected areas;

FIG. 3 is a schematic view of projected areas;

FIG. 4 is a perspective view of a detachable heater in combination withthe one embodiment of a wound treatment device;

FIG. 5 is an exploded view of the one embodiment of a wound treatmentdevice;

FIG. 6 is an exploded view of another embodiment of a wound treatmentdevice;

FIG. 7 is a perspective view of a heater system;

FIG. 8 is an electrical schematic of a pressure sensitive switch for aheater system;

FIG. 9A is an exploded view of a pressure sensitive switch incorporatedinto a wound treatment device;

FIG. 9B is a view of a portion of the pressure sensitive switch;

FIG. 10 is a perspective view of a passive heater embodiment of thewound treatment device;

FIG. 11A is a schematic drawing depicting an alternate geometry for thetransition portion;

FIG. 11B is a schematic drawing depicting an alternate geometry for thetransition portion;

FIG. 11C is a schematic drawing depicting an alternate geometry for thetransition portion;

FIG. 11D is a schematic drawing depicting an alternate geometry for thetransition portion;

FIG. 12A is a schematic drawing depicting functional relationshipsbetween several elements of the invention;

FIG. 12B is a schematic drawing depicting functional relationshipsbetween several elements of the invention;

FIG. 13A is a schematic drawing depicting functional relationshipsbetween several elements of the invention;

FIG. 13B is a schematic drawing depicting functional relationshipsbetween several elements of the invention;

FIG. 14A is a schematic drawing depicting functional relationshipsbetween several elements of the invention;

FIG. 14B is a schematic drawing depicting functional relationshipsbetween several elements of the invention;

FIG. 15 is a perspective view of the preferred embodiment of a flexiblenon-contact wound treatment device that embodies our invention;

FIG. 16 is a perspective view of a detachable heater in combination withour preferred embodiment;

FIG. 17 is an exploded view of our preferred embodiment;

FIG. 18A is a cross-sectional perspective view of our preferredembodiment of the present invention;

FIG. 18B is the cross-sectional perspective view of our preferredembodiment showing the operation of a membrane in adapting the woundtreatment device to body motion;

FIG. 18C is a magnified partial cross-sectional view of our preferredembodiment showing further operation of the membrane in accommodatingbody motion;

FIG. 19A is a side elevational view of the cross-sectional view of FIG.18B when attached to a human patient; and

FIG. 19B is a side elevational view representing the cross-sectionalview of FIG. 18C.

DETAILED DESCRIPTION

For an understanding of the invention that is disclosed and claimed inthis application, reference is made to FIGS. 1-10 in which embodimentsand elements of a wound treatment device are illustrated. With referenceespecially to FIG. 1, a wound treatment device 10 has a planar uppersurface displaced above the skin surface of the patient or person havinga wound that is being treated by application and operation of the device10. The wound treatment device 10 further includes an attachment surfacegenerally held in a plane or surface that is coincident with the planeor surface of the person's skin. Together these two surfaces define anenclosed, non-contact volume over a wound treatment site.

The wound treatment device 10 that is illustrated in FIG. 1 may beconsidered in a general way for the purpose of description. In thisregard, the description of a wound treatment device is aided byconsidering three separate parts of the wound treatment device 10. Theseparts are an attachment portion 12, a wound treatment portion 14, and atransition portion 16. Each portion is designed to serve a separatefunction.

The attachment portion 12 is used to connect the wound treatment device10 to the skin of a patient. The wound treatment portion 14 of the woundtreatment device 10 defines a vertical extent or dimension of the woundtreatment device 10, and thus defines the location of the attachmentsurface. The transition portion 16 connects the attachment portion 12 tothe wound treatment portion 14. The transition portion 16 is provided toimprove the comfort and utility of the wound treatment device 10 whenthe patient moves and stretches the device.

FIG. 1 is a perspective view of a wound treatment device 10 applied to apatient's skin surface 18. A coordinate system 11 is depicted on thepatient's skin surface 18 and it defines X, Y and Z directions. Anattachment portion 12 is formed as an planar rim or flange. Thisattachment portion 12 is attached to the patient's skin 18 with anadhesive and it lies in a first XY plane. In this embodiment of woundtreatment device 10, a transition portion 16 is integrally formed withattachment portion 12. Transition portion 16 rises from the skin surfacein the Z direction to connect to a wound treatment portion 14. In thisembodiment, wound treatment portion 14 has a transparent planar woundcover 20 which allows one to see a wound treatment area 28. Wound cover20 is supported above the first XY plane by a foam ring standoff 15.Wound cover 20 lies in a second XY plane that is vertically displacedalong the Z-axis by foam ring standoff 15 from the first XY plane. Woundcover 20 and foam ring standoff 15 together form wound treatment portion14. The region over wound treatment area 28 is called a wound treatmentvolume 24.

In this figure, wound treatment device 10 has been applied to apatient's skin and is in a relaxed state. In this unstressed state onecan see an outer periphery 22 of attachment portion 12. An innerperiphery 23 is shown by a crease in the structure where it connects totransition portion 16.

FIG. 2 and FIG. 3 should be considered together where they show theinfluence of patient motion on wound treatment device 10. Both FIG. 2and FIG. 3 are top views of wound treatment device 10 of FIG. 1 with thevarious portions of wound treatment device 10 projected onto the firstXY plane.

In FIG. 2, the wound covering is shown in a relaxed and un-stretchedstate having a nominal total projected area 27. Projected woundtreatment area 28 is shown at the center of the wound treatment device10. The outline of foam ring standoff 15 may be seen as the crosshatcharea bounded by an exterior perimeter 25 of foam ring standoff 15, andan interior perimeter 26 of foam ring standoff 15. A transition portionprojected area 17 is bounded by inner periphery 23 of attachment portion12, and interior perimeter 26 of foam ring standoff 15. An attachmentportion projected area 40 is shown as that cross hatched area bounded byouter periphery 22 and inner periphery 23 of attachment portion 12.

FIG. 3 shows wound treatment device 10 stretched along the X-axis bypatient motion. In comparison to FIG. 2, the overall or total projectedarea 27 of wound treatment device 10 has increased. Attachment portionprojected area 40 has increased slightly as attachment portion 12 moveswith the underlying skin. Projected wound enclosure area 28 isessentially unchanged in area since in this embodiment foam ringstandoff 15 is free move against the skin. The largest percentage areachange occurs in transition portion projected area 17. As woundtreatment device 10 deforms in response to patient motion, transitionportion 16 is compliant and pays out material permitting the majority ofthe increase in total projected area 27 to be accommodated primarily bytransition portion projected area 17.

FIG. 4 shows a detachable heater 32 positioned for insertion into apocket formed by pocket cover 21. Pocket cover 21 is bonded to woundcover 20 and is sized to retain heater 32. Foam ring standoff 15 andwound cover 20 serve to stabilize the shape of wound treatment device 10while transition portion 16 accommodates patient motion. Consequently,heater 32 is reliably and comfortably positioned above the woundsurface. In general, it is desirable to use a planar heater as heater 32which has a prescribed heat output per unit area. This form of heaterresults in a more uniform flux of radiant energy applied to the wound.The amount of heat supplied to the wound area is largely independent ofthe height of heater 32 above the wound surface within the range offunctional heights of this device. In some cases, non-uniform wound areaheating might be desirable and therefore the watt density of the heatermay be non-uniform across its surface.

FIG. 5 is an exploded view of the first embodiment of wound treatmentdevice 10. Attachment portion 12 and transition portion membrane 36 areformed as a unitary composite shell 38. Composite shell 38 may be vacuumformed from closed cell polyolefin foams such as Volara-6AS, which is apolyethylene material as sold by Illbruck Inc., of Minneapolis, Minn. Itshould be apparent that many other materials may be substituted withinthe scope of the invention. Foam ring standoff 15 may be die cut fromfoam sheeting of a reticulated polyurethane foam. The absorbency of thefoam as well as its mechanical properties can be tailored to theparticular wound treatment application. For example, the foam standoffmay be impregnated with a medicament such as an antibiotic, antifungal,or antimicrobial material. It may also be desirable to supply adeodorant material or nitric oxide releasing material from the foamstandoff. Wound cover 20 and wound pocket 21 may be made from a thinfilm of polyethylene. In general, the composite shell should besufficiently self supporting so that when wound treatment device 10 isremoved from its release liner, wound treatment portion 14 is held up orsupported by the shaped flexion joint of transition portion membrane 36,and some effort is required to evert composite shell 38 and turn itinside out. This behavior defines the self supporting feature whichcauses foam ring standoff 15 to lie gently against the skin even whenwound treatment device 10 is upside down. For larger wound coverings itmay be desirable to apply a tacky adhesive to the patient contactsurface of the standoff.

FIG. 6 is an exploded view of another embodiment of wound treatmentdevice 10. Attachment portion 12 and transition portion membrane 36 areformed as a unitary composite shell 38. In this embodiment, the woundtreatment volume is defined by a serrated cup standoff 34. Standoff 34may be made from a more rigid polymeric material, such as polyethylene,or the like. The serrations typified by a plurality of serrations 44permit serrated cup standoff 34 to flex and accommodate patient motion.This embodiment shows a release liner 42 coupled to attachment portion12 of composite shell 38 with an adhesive 46. In this embodiment, pocketcover 21 is bonded to composite shell 38.

FIG. 7 depicts a portable power supply 48 to provide for the ambulatoryuse of the heated versions of the wound treatment device. A collectionof battery cells may be wired together to form power supply 48 which maybe conveniently attached to a belt 49. A suitable cable 50 may be usedto conduct power to heater 32. In many instances, it may be desirable tocut off power to heater 32 if wound treatment device 10 is collapsedagainst the wound so as to prevent overheating of the wound surface.

FIG. 8 shows a schematic representation of a touch switch 52 which maybe incorporated directly into detachable heater 32. Heater 32 includes acontinuous resistive heating coil 51. A conductive membrane makes uptouch switch 52 and is arranged near heating coil 51 so that it may"short out" segments or portions of coil 51 it touches. In use, allpower to heating coil 51 is completely turned off by pressure applied toan entire touch sensor 53.

FIG. 9A shows an exploded version of heater 32 incorporating a touchswitch 52 of the type described schematically in FIG. 8. A switch cover45 has a conductive membrane which is located over the conductivepattern of heating coil 51. It is held in position with an adhesive band54. FIG. 9B shows the underside of switch cover 45 showing a pluralityof discrete insulation bumps typified by a bump 47 which serve to spaceand support touch switch 52 above heating coil pattern 51. Pressuresupplied to switch cover 45 inactivates heater coil 51.

FIG. 10 shows an accessory device 55 or cover. This may take the form ofa passive heater (or insulator) with a reflective surface facing thewound. Accessory device 55 may also take the form of a mapping gridwhere a grid work of lines is positioned on a transparent card to permittracking of the wound healing process.

FIG. 11A through FIG. 11D should be considered together. These drawingsfacilitate a description of the connection of the various structures ofthe invention and represent several alternative connection geometries.In general, to accommodate patient motion, the transition portion paysout stored material to increase the projected area of the transitionportion. Each of these drawings represents a mechanical schematic crosssection of a wound treatment device 10 in the XZ plane. In each Figure,the wound covering is in the relaxed state.

FIG. 11A shows a schematic view of a ring standoff 15 extending from afirst plane 56 to a second plane 58. Transition portion 16 has atransition portion membrane 60 which is coupled to attachment portion 12by a first flexible connection 62 formed at the intersection ofattachment portion 12 and transition portion 16. Transition portionmembrane 60 is connected to treatment portion 14 at a second flexibleconnection 64 which is formed at the intersection of transition portion16 and wound treatment portion 14. Wound treatment portion 14 isgenerally a cylindrical cup-shaped structure defining a wound treatmentarea on the patient skin surface. A minimum interconnection distance 66is depicted as a dashed line extending from first flexible connection 62to second flexible connection 64. The length of minimum interconnectiondistance 66 can be used to characterize the "length" of transitionportion membrane 60. For many embodiments of the invention, the lengthof transition portion 16 between first flexible connection 62 and secondflexible connection 64 is greater than the length of the straight linedrawn between these points. This relationship is true for manyembodiments of the wound treatment device when they are in the relaxedor unstressed position. It should be noted that the vertical distancebetween first plane 56 and second plane 58 represents a minimum valuefor minimum interconnection distance 66. In the XY plane, first flexibleconnection 62 forms a first perimeter 61 and a second perimeter 63. Inthe embodiment depicted in FIG. 11 A, first perimeter 61 is larger thansecond perimeter 63.

FIG. 11B is a mechanical schematic diagram which represents a crosssection of another embodiment of the wound treatment device 10 with analternate connection geometry. In this drawing, wound cover 20 extendsradially beyond wound treatment volume 24 so that a second perimeter 68is greater than a first perimeter 71. This generates a reflex transitionportion 74 construction which may be adopted to increase the "length"and amount of material in the reflex transition portion 74.

FIG. 11C shows a construction where a first perimeter 76 and a secondperimeter 78 have approximately the same value and are both concentricwith an axis 90. This construction can produce an undulated transitionportion 77. Once again, the length of undulated transition portion 77exceeds the length of a line 65 between first perimeter 76 and secondperimeter 78.

FIG. 11D shows a hemispheric shell 70 as wound treatment portion 14. Inthis embodiment a second perimeter 80 is a single line of attachmentthat is generally concentric with axis 90. In this embodiment, a firstperimeter 81 has a length which greatly exceeds the length of secondperimeter 80. This construction forms a hemispheric transition portion79 which has a length which exceeds the linear distance between secondperimeter 80 and first perimeter 81 along a line 85.

Although the various geometries vary in detail, it is preferable to formtransition portion 16 from a resilient material which is generallyself-supporting, yet sufficiently flexible so that it acts as acompliant hinge mechanism. This flexibility substantially limits thetransfer of shearing force from wound treatment portion 14 to attachmentportion 12 of the wound treatment device 10, and visa versa. With thegeometries set forth in FIG. 11A through FIG. 11D, transition portion 16of wound treatment device 10 forms a shaped flexion joint or formedexpansion joint which stores "material" in a pleat, convolution,bellows, or the like. This type of structure provides a means forexpanding the size of transition portion 16 resulting in minimizing thetransfer of forces from attachment portion 12 to wound treatment portion14.

FIG. 12A through FIG. 14B should be considered together. In theseembodiments of the invention, the standoff structure reduces in heightresulting in increased transition portion projected area 17 during thestretching of the wound treatment device.

FIG. 12A shows a part of a wound treatment device having foam ringstandoff 15 in the unstressed or relaxed state. In this instance,transition portion projected area 17 is proportional to a dimension 88.In FIG. 12B, the wound treatment device has been stretched and theheight of foam ring standoff 15 is reduced in the Z direction which hasincreased transition portion projected area 17 as represented bydimension 91.

FIG. 13A shows a part of a wound treatment device having serrated cupstandoff 34 in the unstressed or relaxed state. In this instance,transition portion projected area 17 is proportional to a dimension 98.In FIG. 13B, the wound treatment device has been stretched, and theheight of serrated cup standoff 34 is reduced in the Z direction. Theserrated wall sections splay out to permit the height reduction whichincreases transition portion projected area 17 as represented by adimension 99.

FIG. 14A shows a part of a wound treatment device having foam ringstandoff 15 in the unstressed or relaxed state. However, in thisconstruction attachment portion 12 and a transition portion membrane 96lie entirely in first plane 56. In this instance, transition portionprojected area 17 is proportional to a dimension 94. In FIG. 14B, thewound treatment device has been stretched and the height of the foamring standoff 15 is reduced in the Z direction. This height reductionincreases transition portion projected area 17 represented by adimension 92.

The Invention

Our flexible, non-contact wound treatment device is illustrated in FIGS.15-19B where the same reference numerals specify identical partsthroughout the drawings.

FIG. 15 is a perspective view of a flexible, non-contact wound treatmentdevice 100 for application to a patient's skin surface. An attachmentportion 102 is formed as a collar or flange. This attachment portion 102is for attachment around a wound through an adhesive layer on theunderside of the attachment portion. Our preferred embodiment of woundtreatment device 100 also embraces a wound treatment portion 104 thatincludes a wound cover 105, described below, supported by a supportmember in the form of a standoff 106. A transition portion 108 connectsthe wound treatment portion 104 to the attachment portion 102 andpreferably includes a membrane 110 that extends around an outerperiphery of the support member 106 and is attached to the attachmentportion 102 between inner and outer peripheries thereof.

Referring now to FIGS. 15 and 17, in the wound treatment device 100, theattachment portion 102 is an integrated, unitary assembly preferablyhaving three sections: a foam layer 111, an adhesive film layer 112 on abottom surface of the foam layer 111, and a release liner 113 coveringthe adhesive film layer 112. One or more lines of weakness orperforation 114 are provided on the release liner 113 so that its partsmay be separated and selectably peeled off of the adhesive film layer112, thereby to expose the adhesive film layer 112 a section at a timefor application to a person's skin. The foam layer 111 may comprise anaturally open-celled polyurethane foam. The foam layer 111 ispreferably approximately 1/8" thick. The adhesive film layer 112 maycomprise a high MVTR thin film, pressure sensitive adhesive (PSA)laminate available as a package under the trade name Mediderm fromBertek. The foam layer 111 is heat bonded to the adhesive film layer112. The material of which the adhesive film layer 112 is comprised isselected for a combination of adhesion level, permeability, andconformability (stretching and flexing with the skin) to allow prolongedskin contact, without complications. The release liner 113 is a whiterelease paper coated with a release agent that is provided on theMediderm 3701 product. The perforations or slits 114 are made duringassembly to aid in the removal of the release liner 113 prior toattachment of a wound treatment device to a person.

When 111, 112 and 113 are assembled, the attachment portion 102 is aflexible collar shaped part with an inner periphery portion 111i on anupper surface 111s of the foam layer 111 around an inner perimeter, oredge, 111e. The upper surface 111s faces, and is therefore disposedunder, or beneath, the support member 106. The attachment portion 102further includes an outer perimeter, or edge, 111o.

The wound treatment portion 104 includes the support member 106, whichis preferably a ring of absorbent foam such as a naturally open-celledpolyurethane foam that is selected to have favorable characteristics ofabsorbency, leaking and resevoiring. Such material is available as aproduct sold under the trade name Aquazone from Foamex. The supportmember 106 has an upper surface 107, a lower surface (109 in FIGS.18B-19B), an outer perimeter, or edge, 118 and an inner perimeter, oredge, 119. The thickness of the support member 106 is preferably in arange extending from 1/2" to 5/8", with the exact dimension beingselected to maintain non-contact at wound sites whereby, during use, thefoam ring can compress and conform without the wound cover contactingthe wound. The wound cover 105 in the preferred embodiment includes alayer 120 preferably of 4 mil.-thick clear, flexible polyurethane filmwith favorable characteristics selected, but not limited, to includemoisture vapor transfer, oxygen permeability, and transmission ofinfrared radiation. Such material is available as a product sold underthe trade name Deerfield 6100S. The layer 120 is attached to the uppersurface 107 of the support member 106 by a ring 124 of adhesivecomprising a synthetic rubber-base adhesive such the product sold underthe trade name HL-2306-X by H.B. Fuller Adhesive. When the layer 120 isattached to the upper surface 107 of the support member 106, a perimeterportion 121 of the layer 120 extends out beyond the outer perimeter 118of the support member 106. The wound cover 105 further includes astretcher layer 125 attached to the layer 120 so that the layer 120 issandwiched between the stretcher layer 125 and the upper surface 107 ofthe support member 106. The stretcher layer 125 is a 5 mil-thick planarsheet of (preferably) clear, somewhat flexible polyester film havingenough stiffness to aid in maintaining planarity of the wound treatmentportion 104. The function of the stretcher layer 125 is to hold thelayer 120 taut, much as a "stretcher frame" tautens an artist's canvas.The stretcher layer 125 is attached to the layer 120 by a layer 126 ofadhesive comprising a clear flexible polyester carrier film coated onboth sides with an aggressive adhesive. The adhesive layer 126 isoriented over the support member 106. A film carrier allows for theadhesive to be run in a web process and die cut during manufacturing ofthe stretcher layer 125. The stretcher layer 125 further includes a pairof slits 128 that receive a detachable heater. With the provision of theslits 128, a pocket is formed between the stretcher layer 125 and thelayer 120.

The transition portion 108 includes a lower collar 130 that ispreferably formed from the same material as the layer 120. Thetransition portion 108 also includes the outer perimeter portion 121 ofthe layer 120 that extends out beyond the support member 106 whenassembled thereto. When the wound treatment device 100 is assembled, acircumferential edge 122 of the layer 120 is joined to a correspondingcircumferential edge 132 of the lower collar 130. Preferably, the edges122 and 132 are sealed or welded together by a heat process. When sojoined, the outer perimeter portion 121 of the layer 120 and the lowercollar 130 form the membrane 110, which extends over the outside of theouter perimeter 118 of the support member 106. The lower collar has aring-like shape that includes an inner periphery 131. An inner peripheryportion 133 comprises an annular portion of the lower collar material ona surface of the lower collar that faces away from the lower surface 109of the support member 106. The lower surface 109 is not shown in FIG.17, but may be seen in FIGS. 19A and 19B.

The membrane 110 of the transition portion 108 is attached to theattachment portion 102 by heat-bonding or otherwise connecting the innerperiphery portion 133 of the lower collar 130 at or near the opposinginner periphery portion 111i of the attachment portion 102.

Many variations of the assembly illustrated in FIGS. 15 and 17 arepossible. For example, the support member 106 could be contained withinthe structure formed by the layer 120, lower collar 130, and attachmentportion 102, unattached to any portion of the structure.

FIG. 16 shows a detachable heater 140 positioned on the wound cover 105within a pocket formed between the layer 120 and the stretcher layer125, with the opening to the pocket provided by one of the slits 128.The wound cover 105, with the heater 140 contained within the pocket, issupported substantially in a plane or surface above a wound by thesupport member 106. The heater 140 is generally planar and may beconnected to and powered by a portable power supply such as thatillustrated in FIG. 7.

Refer now to FIGS. 18A-18C in which FIGS. 18A and 18B show details ofthe wound treatment device 100 when assembled and put in use. FIG. 18Aillustrates the relationship of the attachment portion 102 with respectto the support member 106 of the wound treatment portion 104. In thisregard, when the wound treatment device is assembled and placed on aflat surface, the attachment portion 102 and wound treatment portion 104substantially align along the inner perimeters 119 and 111e.

The seal between the inner periphery portion 133 of the lower collar 130and the inner periphery portion 111i of the attachment portion 102 liesbeneath the lower surface of the support member 106. This is the surfacethat is indicated by reference numeral 109 in FIGS. 19A and 19B.Preferably, the seal joining the inner periphery portions 133 and 111iis a continuous, closed-loop seal. Although, for reasons explainedbelow, this is the preferred location of the seal between the lowercollar 130 and attachment portion 102, the inventors contemplate thatthe seal could comprise a substantially continuous, closed-loop traceanywhere between the outer perimeter 111o and inner perimeter 111e ofthe attachment member 102.

In FIGS. 17 and 18A, the seal between the edges 122 and 132 of the layer120 and lower collar 130 is exaggerated as a flange. In practice, theshape of the membrane 110 extending from an upper outer edge 107ue ofthe upper surface 107 to a lower outer edge 118be of the outer perimeter118 is rather elongated, with the flange much less pronounced than shownin FIG. 18A. Of course, the membrane 110 in the extent from the edge107ue all the way down to the seal that joins the inner peripheryportions 133 and 111i is not attached, and is therefore free from,although in close proximity to, the outer perimeter 118, lower edge118be and lower surface 109 of the support member 106.

Referring now to FIGS. 18B-19B, the flexible, non-contact woundtreatment device 100 of this invention is suitable for placement onto askin surface 150 of a patient or person so as to include a selectedwound area 152 that abuts a treatment volume 156 within the woundtreatment device 100. This attachment may be directly to the skinsurface 150, or on another member such as an ostomy ring that is, inturn, mounted or attached to the skin surface 150. As FIGS. 18B-19Bdemonstrate, the flexible, non-contact wound treatment device 100 ofthis invention satisfies the objective previously stated by a capabilityof being conformably attached to an uneven, changing surface supportinga wound treatment portion 104 that remains reasonably or substantiallyplanar in its shape, regardless of body contour or movements. In thisregard, as FIGS. 18B and 19B illustrate, the attachment portion 102operates as a hinge or flexion joint that pivots at the seal between theinner periphery portions 133 and 111i. Relatedly, the attachment portion102 is free to conform to the shape of the skin surface by flexiblydeforming between the inner and outer perimeters 111e and 111o. At thesame time, the wound treatment portion 104 is relatively undeformed sothat the support member 106 is able to support the layer 120 andstretcher layer 125 in a relatively planar orientation with respect tothe wound area 152. In the meantime, the wound treatment device 100forms a barrier between the wound treatment volume 156 and the ambientatmosphere by virtue of the seal between the edges 122 and 132 of thelayer 120 and lower collar 130, and the seal between the inner peripheryportions 133 and 111i. The bottom of the wound treatment device 100 issealed to the skin 150 when the release layer 113 is peeled off so thatthe adhesive film layer 112 seals to the skin surface 150.

FIGS. 18C and 19B illustrate the conformability of the wound treatmentdevice 100 provided by flexion of the membrane 110 in the transitionportion 108. FIGS. 18C and 19B are "snap shots" of the flexible,non-contact wound treatment device 100 after placement as describedabove with reference to FIGS. 18B and 19A and after movement of a bodypart on which the device 100 is placed. In these figures, movement isaccommodated by excess length in the membrane 110. In FIGS. 18C and 19B,the membrane 110 has tensioned along the perimeter 118 to provide strainrelief between the lower edge 118be of the support member 106 and theseal between the inner periphery portions 133 and 111i. In addition, theflexibility of the membrane 110 and its freedom from the outer perimeter118 and lower surface 109 permit a play out of excess length of themembrane 110 that abuts the outer perimeter 118 of the support member106. This moves the membrane 10 into close touching engagement with theouter perimeter 118, while lengthening the amount of membrane 110available between the lower edge 118be and the inner periphery portion111i.

In another aspect, as FIGS. 18C and 19B show, the membrane 110 acts as adouble hinge or a double pleat between the lower edge 118be of thesupport member 106 and the attachment portion 102. A first hinge pivotor pleat is at the seal between 133 and 111i. This hinge permits theattachment portion to pivot toward and away from the wound treatmentportion. The second hinge--at edge 118be--allows the wound treatmentportion to move toward and away from the attachment portion. Manifestly,the same effect could be achieved by attachment of the membrane 110 tothe lower surface 109 inside of the edge 118be.

Three significant advantages result from placement of the attachmentportion 102 beneath the support member 106 of the wound treatmentportion.

First, in plan, the shapes and extents of the bottom surface 109 and theattachment portion 102 align and largely overlap, thereby reducing the"foot print" of the wound treatment device 100 to a single,substantially annular shape from the two concentric shapes of FIGS. 2and 3.

Next, the double hinge (or pleat) provided by the membrane 110 increasesthe conformability of the wound treatment device to shape and movement,while maintaining the planarity of the wound cover and preventing itscontact with a wound.

Last, the lower collar 130, in extending substantially to the innerperimeter 111e of the attachment portion 102 forms a barrier to moistureand wound exudate which may be absorbed by the support member 106,thereby reducing maceration of skin underneath the attachment portion102.

While the invention has been illustrated by means of specificembodiments and examples of use, it will be evident to those skilled inthe art that many variations and modifications may be made thereinwithout deviating from the scope and spirit of the invention. However,it is to be understood that the scope of the present invention is to belimited only by the appended claims.

We claim:
 1. A non-contact wound treatment device, comprising:a flexibleattachment portion including an outer perimeter and an inner perimetersurrounded by the outer perimeter; a wound treatment portion including awound cover and a support member supporting the wound cover; and atransition portion including a flexible membrane connecting the woundtreatment portion to the attachment portion, the membrane acting betweenthe support member and the attachment portion and attached to theattachment portion between the inner and outer perimeters of theattachment portion.
 2. The non-contact wound treatment device of claim 1wherein the support member has an outer perimeter and the membraneextends around the outer perimeter of the support member.
 3. Thenon-contact wound treatment device of claim 1 wherein the membrane isattached to the attachment portion near the inner perimeter of theattachment portion.
 4. The non-contact wound treatment device of claim3, wherein the support member is a ring that includes an inner perimetersubstantially aligned with the inner perimeter of the attachmentportion.
 5. The non-contact wound treatment device of claim 1, whereinthe inner perimeter of the attachment portion is surrounded by the outerperimeter of the support member.
 6. The non-contact wound treatmentdevice of claim 1, wherein the inner perimeter of the attachment portionis beneath the support member.
 7. The non-contact wound treatment deviceof claim 6, wherein the membrane is attached to the attachment portionnear the inner perimeter of the attachment portion.
 8. The non-contactwound treatment device of claim 4, wherein the ring has an upper surfacesupporting the wound cover and a lower surface facing the attachmentportion, and:the inner perimeter of the attachment portion is beneaththe ring; and the membrane is attached to the upper surface.
 9. Thenon-contact wound treatment device of claim 8, wherein:the wound coverincludes a layer of flexible material attached to the upper surface; aperipheral portion of the layer of flexible material extends beyond theupper surface; and the membrane comprises a collar of flexible materialhaving an outer edge joined to the peripheral portion and an innerperimeter joined to the attachment portion near the inner perimeter ofthe attachment portion.
 10. The non-contact wound treatment device ofclaim 8, wherein the ring comprises a foam material.
 11. The non-contactwound treatment device of claim 10, wherein the foam material is anabsorbent foam material.
 12. The non-contact wound treatment device ofclaim 9, the wound cover further including a substantially planar layerof flexible material joined to the layer of flexible material above theupper annular surface.
 13. The non-contact wound treatment device ofclaim 12 further including a slit in the substantially planar layer, theslit opening into a pocket formed by the substantially planar layer andthe layer of flexible material.
 14. The non-contact wound treatmentdevice of claim 13 further including a heater disposed in the pocket.15. The non-contact wound treatment device of claim 14, furtherincluding a power supply connected to the heater.
 16. The non-contactwound treatment device of claim 1, wherein the attachment portioncomprises a layer of foam material.
 17. The non-contact wound treatmentdevice of claim 16, wherein the attachment portion further includesadhesive material carried on a surface of the layer of foam material anda release layer carried on the adhesive material.
 18. The non-contactwound treatment device of claim 17 wherein the release layer has one ormore lines of weakness for permitting a portion of the release layer tobe removed from the adhesive material.
 19. The non-contact woundtreatment device of claim 16, wherein the layer of foam materialcomprises open-cell foam material.
 20. The non-contact wound treatmentdevice of claim 1, wherein the attachment portion has substantiallycollar-like shape and is disposed beneath the wound treatment portion.21. The non-contact wound treatment device of claim 1, wherein the woundcover is substantially planar.
 22. A non-contact wound treatment device,comprising:a flexible attachment portion including an outer perimeterand an inner perimeter surrounded by the outer perimeter; a woundtreatment portion including a wound cover and a support member with afirst surface supporting the wound cover and a second surface facing theattachment portion; and a member with at least one hinge acting betweenthe second surface and the attachment portion and attached to theattachment portion between the outer perimeter and the inner perimeter.23. The non-contact wound treatment device of claim 22, wherein themember includes a double hinge having a first pivot near the innerperimeter of the attachment portion and a second pivot near an edge ofthe second surface.
 24. The non-contact wound treatment device of claim23, wherein the member comprises a membrane.
 25. The non-contact woundtreatment device of claim 24, wherein the membrane is attached to theattachment portion near the inner perimeter.
 26. The non-contact woundtreatment device of claim 25, wherein the support member is a ring thatincludes an inner perimeter aligned with the inner perimeter of theattachment portion.
 27. The non-contact wound treatment device of claim26, wherein the ring comprises a foam material.
 28. The non-contactwound treatment device of claim 27, further including a heater on thewound cover.
 29. The non-contact wound treatment device of claim 22,further including a heater on the wound cover.
 30. The non-contact woundtreatment device of claim 28 or 29, further including a power supplyconnected to the heater.
 31. The non-contact wound treatment device ofclaim 22 wherein the wound cover is substantially planar.
 32. Anon-contact wound treatment device, comprising:a flexible attachmentportion including an outer perimeter and an inner perimeter surroundedby the outer perimeter; a wound treatment portion including a woundcover and a support member with a first surface supporting the woundcover and a second surface facing the attachment portion; and at leastone flexion joint acting between the second surface and a portion of theattachment portion near the inner perimeter.
 33. The non-contact woundtreatment device of claim 32, wherein the at least one flexion jointincludes a member having a first pivot near the inner perimeter of theattachment portion and a second pivot near an edge of the secondsurface.
 34. The non-contact wound treatment device of claim 33, whereinthe flexion joint comprises a membrane.
 35. The non-contact woundtreatment device of claim 34, wherein the membrane is attached to theattachment member near the inner perimeter.
 36. The non-contact woundtreatment device of claim 35, wherein the support member is a ring thatincludes an inner perimeter aligned with the inner perimeter of theattachment member.
 37. The non-contact wound treatment device of claim36, wherein the ring comprises a foam material.
 38. The non-contactwound treatment device of claim 37, further including a substantiallyplanar heater on the wound cover.
 39. The non-contact wound treatmentdevice of claim 32, further including a substantially planar heater onthe wound cover.
 40. The non-contact wound treatment device of claim 32or 39, further including a power supply connected to the substantiallyplanar heater.
 41. The non-contact wound treatment device of claim 32wherein the wound cover is substantially planar.